1. Field of the Invention
The present invention relates to a power control apparatus and method for preventing a system from being repeatedly booted and shut off by re-setting a cut-off voltage when the system is shut down by a cutoff mode.
2. Description of the Related Art
Recently, a terminal device has a function of making a backup of working contents and automatically shutting down a system (hereinafter, referred to as a ‘cutoff mode’) when the battery of the terminal device is discharged below a predetermined value.
However, voltage of the battery varies according to loads on the central processing unit (CPU) and peripheral systems.
Accordingly, the prior art has the following problems.
That is, in a case where the system has been shut down by the cutoff mode while it is driven, the voltage of the battery is measured relatively high if the terminal device is driven until all peripheral devices are driven. Therefore, as the system has been driven and the load of the system is increased after a while, the voltage of the battery falls below the cutoff voltage. Thus, the system is again shut down by the cutoff mode.
Further, the prior art has a problem in that the system is repeatedly booted and shut down and thus the battery and system are excessively damaged.
In addition, since the battery is pre-charged in a low voltage state, the system is repeatedly turned on or off until the voltage of the battery is discharged to the bottom. Therefore, there is another problem in that charging time is extended (the aforementioned pre-charging is performed at a rate of 0.1 times as fast as the general charging).